TECHNICAL FIELD
[0001] The present invention relates to a print adhesive label and an adherend using the
same. More specifically, the present invention relates to a print adhesive label and
an adherend using the same, which are useful as a security label.
BACKGROUND ART
[0002] In order to prevent unauthorized opening and forgery, a security label is used for
various products such as a television, a computer and a vehicle. For example, Patent
Literature 1 discloses a security label for applying an identifier pattern such as
a code, a personal identification number or a vehicle registration number to an adherend,
wherein a barrier medium configured to form the identifier pattern is located on an
adhesive layer, and the barrier medium selectively blocks diffusion of an identifier
medium such as a UV fluorescent dye in the adhesive agent into the adherend. As shown
in FIG. 6 of the present application, using the security label of Patent Literature
1, the identifier pattern can be applied to the adherend by removing an adhesive label
from a plastic plate (the adherend) to which the security label is pasted and then
irradiating the plastic plate with a black light. However, as shown in FIG. 5 of the
present application, in the case where designable printing, etc. is performed on the
adherend such as a product, an opaque substrate used on the label substrate, or information
printed on the label substrate, imparts unnecessary concealment, and the designability
of the appearance of the adherend is impaired.
CITATION LIST
PATENT LITERATURE
SUMMARY OF THE INVENTION
TECHNICAL PROBLEM
[0004] There has been a need for a method of providing security wherein a pasted security
label is inconspicuous and is invisible to consumers' eyes from the viewpoint of the
designability of the appearance, in a clothing ornament such as a clothing, an accessary,
and a high value product such as an electrical appliance, a furniture, etc. Therefore,
an object of the present invention is to provide a print adhesive label and an adherend
using the same, wherein the pasted security label is inconspicuous, and security is
provided without being visible to consumers' eyes, and the designability of the appearance
is not impaired.
SOLUTION TO THE PROBLEM
[0005] The present inventor has done intensive studies to solve the above problems, and
has found that the above problems are solved by a print adhesive label comprising
a release sheet consisting of a release sheet substrate and a release layer, and an
adhesive label consisting of a label substrate and an adhesive layer, wherein a print
layer with information printed is provided between the release layer and the adhesive
layer; the adhesive layer comprises a fluorescence dye; the adhesive layer is pasted
on the release layer and the print layer; a surface of the adhesive layer has a region
where the print layer does not exist in a planar view; the label substrate is a transparent
plastic film; and the adhesive layer is transparent. As a result, the present invention
has been completed. That is, the present invention is as follows.
- [1] A print adhesive label comprising a release sheet consisting of a release sheet
substrate and a release layer, and an adhesive label consisting of a label substrate
and an adhesive layer,
wherein a print layer with information printed is provided between the release layer
and the adhesive layer;
the adhesive layer comprises a fluorescence dye;
the adhesive layer is pasted on the release layer and the print layer;
a surface of the adhesive layer has a region where the print layer does not exist
in a planar view;
the label substrate is a transparent plastic film; and
the adhesive layer is transparent.
- [2] The print adhesive label according to [1], wherein the label substrate is a vulnerable
substrate.
- [3] The print adhesive label according to [1] or [2], wherein the print layer is transparent.
- [4] The print adhesive label according to any one of [1] to [3],
wherein adhesive transfer does not occur from the adhesive layer, when the release
sheet is removed from the adhesive label, and the adhesive layer is pasted on an adherend,
and the adhesive label is removed from the adherend.
- [5] The print adhesive label according to any one of [1] to [4], wherein the print
layer is not embedded in the adhesive layer, when the release sheet is removed from
the adhesive label.
- [6] An adherend pasted with the print adhesive label according to any one of [1] to
[5] from which the release sheet is removed.
- [7] The adherend obtained by removing the adhesive label from the adherend according
to [6],
wherein the fluorescence dye transfers to a region of the adherend except for a region
of the adherend attached to the print layer.
ADVANTAGEOUS EFFECTS OF THE INVENTION
[0006] When the adhesive label is pasted on an adherend such as a product using the print
adhesive label of the present invention, since the label substrate and the adhesive
layer are transparent, the pasted adhesive label is inconspicuous and the designability
of the adherend is not impaired. Since the adhesive layer comprises the fluorescent
dye, the entire adhesive layer emits light by irradiating the adherend on which the
adhesive label is pasted with a black light (an ultraviolet lamp, etc.) through the
adhesive label, and security can be provided without being visible. In addition, by
making the print layer be colored, information on the print layer can be seen through
the adhesive label. On the other hand, by making the printing layer be transparent,
the label substrate, the adhesive layer and the print layer are optically integrated,
and the adherend is visually recognized as it is, so that deterioration of the designability
of the adherend can be further reduced. Furthermore, when the adhesive label pasted
on the adherend is removed from the adherend, the fluorescent dye transfers to a region
where the print layer does not exist on the surface of the adhesive layer in a planar
view, that is, to a region of the adherend except for the region of the adherend attached
to the print layer. Therefore, information of the print layer can be confirmed as
white spots as a reverse image (in a state in which the fluorescent dye does not develop
color) by irradiating a black light. When the print layer is transparent, information
on the print layer cannot be visually confirmed, but when the adhesive label pasted
on the adherend is removed from the adherend, information on the print layer can be
confirmed as white spots as a reverse image (in a state where the fluorescent dye
does not develop color) by irradiating a black light, and thereby security can be
further improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007]
FIG. 1 shows a conceptual diagram which schematically shows the print adhesive label
of the present invention, in the state where the release sheet and the adhesive label
are pasted.
FIG. 2 shows a conceptual diagram which schematically shows a method of producing
the print adhesive label of the present invention.
FIG. 3 shows a conceptual diagram of the print adhesive label of the present invention
from which the release sheet is removed.
FIG. 4 shows a conceptual diagram of the adherend on which the print adhesive label
of the present invention from which the release sheet is removed is pasted.
The fluorescence dye transfers to a region of the adherend except for a region of
the adherend attached to the print layer.
FIG. 5 shows a photograph of the conventional security label, which was taken from
the label substrate side.
FIG. 6 shows a photograph of the polypropylene plate (adherend) irradiated with a
black light, which was obtained by pasting the conventional security label on a polypropylene
plate and removing the adhesive label from the polypropylene plate.
DESCRIPTION OF THE INVENTION
<Print adhesive label>
[0008] As shown in FIG. 1, the print adhesive label of the present invention is a print
adhesive label comprising the release sheet 7 consisting of the release sheet substrate
6 and the release layer 5, and the adhesive label 3 consisting of the label substrate
1 and the adhesive layer 2, wherein the print layer 4 with information printed is
provided between the release layer 5 and the adhesive layer 2; the adhesive layer
2 comprises the fluorescence dye 9; the adhesive layer 2 is pasted on the release
layer 5 and the print layer 4; the surface of the adhesive layer 2 has a region where
the print layer 4 does not exist in a planar view; the label substrate 1 is a transparent
plastic film; and the adhesive layer 2 is transparent. In the present specification,
"transparent" does not mean only colorless transparent, but also includes colored
transparent or translucent. In other words, everything is referred to as "transparent",
as long as its internal state can be visually recognized by the naked eyes. The same
applies to matters in the following description.
(Release sheet 7)
[0009] The release sheet 7 is composed of the release sheet substrate 6 and the release
layer 5. The release sheet substrate 6 has a function of supporting the release layer
5. The release sheet substrate 6 is composed of, for example, a polyester film such
as a polyethylene terephthalate film and a polybutylene terephthalate film; a polyolefin
film such as a polypropylene film, a polyethylene film and a polymethylpentene film;
a plastic film such as a polycarbonate film and a polyvinyl chloride film; a metal
foil such as aluminum and stainless steel; a paper base material such as glassine
paper, kraft paper, coated paper and fine paper; an impregnated paper such as dust-free
paper and drawing paper; a laminated paper base material such as a single-sided polyethylene
laminated fine paper, a double-sided polyethylene laminated fine paper, a single-sided
polyethylene laminated glassine paper and a double-sided polyethylene laminated glassine
paper; a paper such as a synthetic paper; a laminated product thereof, and the like.
When the print layer 4 is printed on the release sheet 7 with a laser printer or the
like, the release sheet substrate 6 may contract due to heat when the toner image
is fixed to the release layer 5 in the release sheet 7, and the release sheet 7 may
curl. In case that the release sheet 7 is likely to curl by heat when the print layer
4 is printed, in order to prevent curl, the release sheet 7 is preferably one that
does not curl by heat. Curl of the release sheet 7 by heat can be prevented by using,
for example, a polyester film, a single-sided polyethylene laminated fine paper, a
double-sided polyethylene laminated fine paper, or the like, as the release sheet
substrate 6.
[0010] A thickness of the release sheet substrate 6 is not particularly limited, but is
usually 20 to 200 µm, preferably 25 to 100 µm.
[0011] Examples of a release agent used for the release layer 5, include a silicone release
agent, a non-silicone release agent and the like. Examples of the silicone release
agent, include an addition silicone produced by an addition reaction of an organopolysiloxane
containing aliphatic unsaturated groups and an organohydrogenpolysiloxane using a
platinum compound as a catalyst; and a condensation silicone produced by a condensation
reaction of an organopolysiloxane using a metal organic acid salt catalyst such as
an organotin compound. These silicone compositions may be appropriately used as a
solvent type composition in which the silicone is dissolved in an organic solvent
such as toluene, an emulsion type composition in which the silicone is emulsified,
or a solvent-free type composition consisting only of the silicone.
[0012] Examples of the non-silicone release agent, include a polyolefin such as a polyethylene,
a thermoplastic elastomer such as an olefinic thermoplastic elastomer, a fluororesin
such as a tetrafluoroethylene, a wax, an alkyd resin, and a mixture thereof.
[0013] The release layer 5 may contain other various additives such as another resin component,
a plasticizer and a stabilizer. A thickness of the release layer 5 is not particularly
limited, but is preferably 0.1 to 50 µm, more preferably 0.3 to 30 µm. When the thickness
of the release layer 5 is thinner than 0.1 pm, the peelability is inferior. When the
thickness of the release layer 5 is thicker than 50 µm, the peelability is not improved
and it is uneconomical.
(Print layer 4)
[0014] Information provided by the print layer 4, includes fixed information and/or variable
information. The fixed information and/or variable information may be information
that imparts security for prevention of unauthorized opening and forgery to the adherend
8 of various products such as a television, a computer and a vehicle. Examples of
the fixed information include a company name and a product name. Examples of the variable
information include a predetermined number of set of labels, different information
for each label, a lot number, a serial number, a production date, and the like.
[0015] The print layer 4 has a function of inhibiting transfer of the fluorescence dye 9
contained in the adhesive layer 2 to the adherend 8. That is, the fluorescence dye
9 contained in the adhesive layer 2 transfers to a region of the adherend 8 except
for a region of the adherend 8 attached to the print layer 4. Then, the information
of the print layer 4 is confirmed as white spots as a reversed image (in a state where
the fluorescent dye 9 does not develop color) by irradiating the adherend 8 with a
black light. Examples of a printing method for forming the print layer 4, include
a laser printer, a thermal transfer printer, screen printing, a typewriter, an ink
jet printer, a UV printer, and the like. The method is preferably a laser printer,
a laser printers using a carbon dioxide laser, or the like.
[0016] One or more of various colors may be used in the print layer 4. Moreover, the transparent
print layer 4 may be used singly, or in combination with the print layer 4 having
various colors. The transparent print layer 4 can be formed by using, for example,
a colorless transparent ink, a colored transparent ink, or the like. The print layer
4 is preferably colorless and transparent from the viewpoint of further improving
security and the designability. By making the print layer 4 colorless and transparent,
information on the print layer 4 cannot be seen with the naked eyes in the state of
the adhesive label 3 pasted on the adherend 8. In addition, since information printed
on the adherend 8 is directly visible through the adhesive label 3 in the state of
the adhesive label 3 pasted on the adherend 8, the designability of the appearance
of the adherend 8 is more retained. Even if a black light (an ultraviolet lamp, etc.)
is irradiated in the state of the adhesive label 3 pasted on the adherend 8, the entire
adhesive layer 2 emits light and the information on the print layer 4 cannot be seen.
Therefore, unless the adhesive label 3 is removed, the information on the print layer
4 is kept secret. On the other hand, by removing the adhesive label 3, white spots
can be confirmed as a reverse image of the print layer 4 (in a state where the fluorescence
dye 9 does not develop color) by irradiating a black light.
[0017] In the print adhesive label of the present invention, it is preferable that the print
layer 4 is not completely embedded in the adhesive layer 2 when the release sheet
7 is removed from the adhesive label 3. Since the print layer 4 is not completely
embedded in the adhesive layer 2, a region where the print layer 4 contacts the adherend
8 and a region where the print layer 4 does not contact the adherend 8 are definitely
divided, when the adhesive label 3 is pasted on the adherend 8. The fluorescence dye
9 contained in the adhesive layer 2 transfers to only a region where the print layer
4 does not contact the adherend 8 (a region where the print layer 4 does not exist
on the surface of the adhesive layer 2 in a plan view, that is, a region of the adherend
8 except for a region of the adherend 8 attached to the print layer 4), so that the
inverted image of the information on the print layer 4 is difficult to blur.
[0018] In order to prevent the print layer 4 from being completely embedded in the adhesive
layer 2, the thickness and material of the print layer 4, or the thickness and material
of the adhesive layer 2 may be adjusted, and the pasting conditions (temperature,
pressure) between the adhesive layer 2 in the adhesive label 3 and the release sheet
7 may be adjusted by optimization, when the print adhesive label of the present invention
is produced by printing the printed layer 4 on the release sheet 7, as described later.
[0019] A thickness of the print layer 4 is preferably 0.5 to 5 pm, more preferably 0.8 to
3 µm. When the thickness of the print layer 4 is less than 0.5 pm, a region where
the print layer 4 contacts the adherend 8 and a region where the print layer 4 does
not contact the adherend 8 are difficult to be definitely divided, when the adhesive
label 3 is pasted on the adherend 8. As a result, the fluorescence dye 9 contained
in the adhesive layer 2 easily transfers to the edge of the region where the print
layer 4 contacts the adherend 8, and the inverted image of the print layer 4 is likely
to blur. When the thickness of the print layer 4 exceeds 5 µm, the adhesive layer
2 is difficult to contact the adherend 8 when the print adhesive label is pasted on
the adherend 8, and the adhesive strength of the print adhesive label may be reduced.
The blur of the reverse image of the print layer 4 due to the transfer of the fluorescence
dye 9 contained in the adhesive layer 2 can be controlled, by further adjusting the
shape of the print layer 4, the font, size or line width, etc. of a character, in
addition to the thickness of the print layer 4. In the present invention, "the print
layer 4 is not completely embedded in the adhesive layer 2" refers to the state that
there is a difference in level between the surface of the print layer 4 which contacts
the release layer 5 and the surface of the region of the adhesive layer 2 where the
print layer 4 does not exist. The difference can be confirmed by removing the release
sheet 7 in the print adhesive label and observing the exposed adhesive layer 2 with
an optical microscope.
(Adhesive label 3)
[0020] The adhesive label 3 is composed of the label substrate 1 and the adhesive layer
2, and commercially available and known adhesive labels may also be used.
[0021] The label substrate 1 has a function of supporting the adhesive layer 2 and may be
a single layer or a multilayer. The label substrate 1 is a transparent plastic film.
The label substrate 1 is composed of, for example, a polyethylene terephthalate film,
a polybutylene terephthalate film, a polyethylene film, a polypropylene film, a polymethylpentene
film, a polycarbonate film, a polyvinyl chloride film, an acrylic resin vulnerable
sheet, an acrylic urethane resin vulnerable sheet, a cellulose resin film such as
a triacetylcellulose, a plastic film such as a polystyrene film and a polyurethane
film. The label substrate 1 may be subjected to a surface treatment to the front surface
or the back surface thereof for the purpose of improving adhesion of the adhesive
layer 2. Since the label substrate 1 and the adhesive layer 2 are transparent, it
is hardly noticeable that the adhesive label 3 is pasted on the adherend 8, and the
information printed on the adherend 8 is visible through the adhesive label 3 as it
is in the state of the adhesive label 3 pasted on the adherend 8, and the designability
of the adherend 8 such as a product is not impaired. In addition, the normal label
cannot be distinguished with the naked eyes in the state of the adhesive label 3 pasted
on the adherend 8, but by irradiating a black light through the adhesive label 3,
light emission by the fluorescence dye 9 can be confirmed. Therefore, security can
be further improved. The label substrate 1 is preferably colorless and transparent
from the viewpoint of further improving security and the designability. A thickness
of the label substrate 1 is not particularly limited, but is preferably about 20 to
200 µm, and more preferably about 25 to 100 µm.
[0022] The label substrate 1 is preferably a vulnerable substrate. By using the vulnerable
label substrate 1, when the adhesive label 3 is removed from the adherend 8, the label
substrate 1 is damaged and cannot be removed cleanly, which is effective for preventing
falsification. Examples of the vulnerable label substrate 1 include a colorless and
transparent acrylic resin vulnerable sheet, acrylic urethane resin vulnerable sheet,
urethane resin vulnerable sheet, polyvinyl chloride, cellulose resin film such as
a triacetyl cellulose, polystyrene film, polyurethane film, and the like.
[0023] The adhesive layer 2 comprises the fluorescence dye 9, and is transparent. The adhesive
layer 2 is preferably colorless and transparent from the viewpoint of further improving
security and the designability. The adhesive layer 2 is composed of an adhesive composition
mainly comprising an adhesive. As the adhesive, a known adhesive such as an acrylic
adhesive, a polyurethane adhesive, an epoxy adhesive, a rubber adhesive, a silicone
adhesive and a polyester adhesive, may be used. The adhesive is preferably an acrylic
adhesive. As the adhesive, an adhesive wherein its adhesive strength to the label
substrate 1 is larger than its adhesive strength to the adherend 8, and its adhesive
strength to the print layer 4 is larger than adhesive strength between the print layer
4 and the release layer 5, can be preferably used. A thickness of the adhesive layer
2 is not particularly limited, and is, for example, 1 to 200 pm, preferably 10 to
100 pm, and more preferably 10 to 50 µm.
[0024] As the adhesive, it is preferable that adhesive transfer does not occur from the
adhesive layer 2 when the adhesive label 3 is removed from the adherend 8 in the state
of the adhesive label 3 pasted on the adherend 8. By no adhesive transfer, it cannot
be acknowledged that the adhesive label 3 was pasted on the adherend 8, unless a black
light is irradiated. Specifically, the adhesive strength of the print adhesive label
of the present invention based on the Japanese Industrial Standard: JIS Z 0237: 2000,
is preferably 2.0 N / 25 mm or more, more preferably 3.0 N / 25 mm or more, under
a condition of 23 °C and 50% RH (relative humidity). The upper limit of the adhesive
strength is preferably, for example, 20 N / 25 mm or less, more preferably 15 N /
25 mm or less, and still more preferably 12.5 N / 25 mm or less. In the present invention,
the value of the adhesive strength refers to a value measured by the following procedure:
preparing a test piece by cutting the print adhesive label to 25 mm × 300 mm; peeling
off the release sheet 7 in the print adhesive label; pasting the test piece to a stainless
steel plate (SUS 304) under a condition of 23 °C and 50% RH (relative humidity) to
obtain a test sample; and measuring the adhesive strength at 24 hours after pasting
at a pulling speed of 300 mm/min by a 180 degree peeling method, based on JIS Z 0237:
2000, under the same condition.
[0025] The fluorescence dye 9 contained in the adhesive layer 2 may be a dye that emits
fluorescence by absorbing an ultraviolet light, such as a diaminostilbene dye, a quinazolone
dye, a perylene dye, a coumarin dye, an oxazole dye, a triazole dye, a carbazole dye,
a pyridine dye, and a naphthalic acid dye and an imidazolone dye, and a fluorescent
generator such as a fluorescein, a thioflavine, an eosin, a rhodamine and a terphenyl,
and the like. One type of these may be used singly, or two or more types of these
may be used in combination. The content of the fluorescence dye 9 contained in the
adhesive layer 2 is usually about 0.1 to 30 parts by mass, preferably about 0.3 to
10 parts by mass, and more preferably about 0.5 to 5 parts by mass, with respect to
100 parts by mass of the solid content of the adhesive, from the viewpoint of a balance
between fluorescence emission and economy. The adhesive layer 2 may contain various
additives such as a plasticizer, a stabilizer, a metal oxide such as titanium dioxide
particles, or the like, in addition to the fluorescence dye 9. By using a metal oxide
such as titanium dioxide particles in combination, the fluorescence emission of the
adherend 8 is less likely to be impaired, when the adhesive label 3 is pasted on the
adherend 8 and then removed from the adherend 8.
<Method of producing print adhesive label>
[0026] A method of producing the print adhesive label of the present invention is demonstrated
based on FIG. 2 schematically showing the method. First, as shown in FIG. 2, the release
sheet 7 consisting of the release sheet substrate 6 and the release layer 5, and the
adhesive label 3 consisting of the label substrate 1 of a transparent plastic film
and the transparent adhesive layer 2 comprising the fluorescence dye 9, are prepared.
The print layer 4 is formed by printing the fixed information and/or variable information
on the release layer 5 in the release sheet 7 by using a laser printer, a thermal
transfer printer, screen printing, a typewriter, an inkjet printer, or an UV printer,
etc. Subsequently, the release sheet 7 on which the print layer 4 is formed, is pasted
on the adhesive layer 2 in the adhesive label 3, so that the print adhesive label
of the present invention can be produced in which the surface of the adhesive layer
2 has a region where the print layer 4 does not exist in a plan view. That is, the
print layer 4 transfers from the release sheet 7 to the adhesive label 3. In addition,
this production method is simply one example, and other methods such as a method of
printing the print layer 4 directly on the adhesion layer 2, may be also used, as
long as the print adhesive label of the present invention is produced.
<Method of using print adhesive label>
[0027] As shown in FIG. 3, the adhesive label 3 having the print layer 4 attached to the
adhesive layer 2 is formed, by removing the release sheet 7 from the print adhesive
label of the present invention. Subsequently, the adhesive label 3 which the print
layer 4 is attached to, is pasted on the adherend 8. Since the surface of the adhesive
layer 2 has a region where the print layer 4 does not exist in a plan view, the adhesive
layer 2 in this region contacts the adherend 8. As shown in FIG. 4, by contacting
the adhesive layer 2 comprising the fluorescence dye 9 with the adherend 8, the fluorescence
dye 9 does not transfer to the adherend 8 in a region where the print layer 4 contacts
the adherend 8, and the fluorescence dye 9 transfers to the adherend 8 in a region
where the print layer 4 does not contact the adherend 8. Since the label substrate
1 and the adhesive layer 2 are transparent in the print adhesive label of the present
invention, it is difficult to notice that the adhesive label 3 is pasted, and the
adherend 8 is visible as it is, and the designability of the adherend 8 is not impaired.
Moreover, since the label substrate 1 and the adhesive layer 2 are transparent, the
entire adhesive layer 2 emits light by irradiating a black light (an ultraviolet lamp,
etc.) in a state where the adhesive label 3 is pasted on the adherend 8, so that security
can be imparted. Further, by making the print layer 4 transparent, information on
the print layer 4 cannot be seen without irradiating a black light (an ultraviolet
lamp, etc.), so that both security and the designability can be achieved.
[0028] The adhesive label 3 is removed from the adherend 8 which the adhesive label 3 which
the print layer 4 is attached to is pasted on. Since the fluorescence dye 9 has transferred
to the obtained adherend 8 in a region where the print layer 4 does not exist on the
surface of the adhesive layer 2 in a plan view, the information of the print layer
4 is confirmed as a reverse image by irradiating a black light. That is, the information
of the print layer 4 is confirmed as white spots (in a state where the fluorescence
dye 9 does not develop color). When a vulnerable substrate is used as the label substrate
1, since the adhesive label 3 cannot be removed cleanly, it is more effective for
preventing falsification.
EXAMPLE
[0029] Hereinafter, the present invention is explained in detail with reference to Examples,
Comparative Examples and Experiments. However, the present invention is not limited
to these Examples, etc.
Example 1
[0030] A release sheet (Lintec Co., Ltd.: 8E) was provided, which had a release layer with
an addition silicone release agent on the polyethylene laminate surface of a release
sheet substrate obtained by laminating a polyethylene on one surface of a fine paper
having a thickness of 79 µm. Then, information consisting of the characters "TEST"
was color-printed on the release layer surface using a laser printer (OKI Europe,
Ltd.: desktop color printer).
[0031] Next, an adhesive label was prepared, which had a colorless and transparent adhesive
layer of an acrylic adhesive comprising 12.7 parts by mass of an oxazole fluorescent
dye (name: 2,5-bis(5-tert-butyl-2-benzoxazolyl) thiophene) with respect to 100 parts
by mass of the solid content, having a thickness of 24 µm on one side of a colorless
and transparent polyester film having a thickness of 50 µm as a label substrate. Then,
the adhesive layer in the adhesive label was pasted on the above printed release layer
surface to prepare a print adhesive label. In addition, the adhesive layer surface
when the release sheet was removed from the print adhesive label, was observed with
an optical microscope, and it was confirmed that the print layer was not completely
embedded in the adhesive layer.
Example 2
[0032] A print adhesive label was prepared in the same manner as in Example 1 except that
the information consisting of the characters "TEST" was printed by colorless and transparent
clear printing on the release layer surface by using a UV printer.
Example 3
[0033] A print adhesive label was prepared in the same manner as in Example 1 except that
the information consisting of the characters "TEST" was printed by colorless and transparent
clear printing on the release layer surface by using a triacetyl cellulose film as
a vulnerable label substrate and by using a UV printer.
Comparative Example 1
[0034] A print adhesive label was prepared in the same manner as in Example 1 except that
an opaque white polyethylene terephthalate film having a thickness of 50 µm was used
as a label substrate.
Experiment 1: Confirmation of the state of a reverse image of the print layer by transfer of the
fluorescence dye
[0035] The release sheets were removed from the print adhesive labels of Examples 1 to 3
and Comparative Example 1. The resulting adhesive labels were pasted on 2 mm thick
polypropylene plates (PP plates) as adherends, on which a 2 kg rubber roller was reciprocated
5 times. After left to stand at room temperature for 24 hours, the adhesive labels
were removed from the PP plates.
[0036] A black light was irradiated to the PP plates, and the states of the information
of the light emitting part by the fluorescent dye transferred to the PP plates were
observed with the naked eyes.
[0037] The PP plates obtained using the print adhesive labels of Examples 1 to 3 and Comparative
Example 1 were observed, and all the character information of the light emitting part
by the fluorescent dye transferred to the PP plates could be recognized, and the reverse
images of the print layers were also not blurred. In case of the print adhesive labels
of Examples 2 and 3 having the colorless and transparent print layers, the character
information of the print layers could not be seen through the adhesive labels unless
the adhesive labels were removed and the PP plates were irradiated with a black light,
and the character information of the print layers was kept secret. Therefore, security
was further higher compared with the print adhesive label of Example 1 having the
colored print layer.
Experiment 2: Confirmation of light emission of the fluorescent dye
[0038] The release sheets were removed from the print adhesive labels of Examples 1 to 3
and Comparative Example 1. The resulting adhesive labels were pasted on 2 mm thick
polypropylene plates (PP plates) as adherends, on which a 2 kg rubber roller was reciprocated
5 times. After left to stand at room temperature for 24 hours, a black light was irradiated
through the adhesive labels, and the light emitting part by the fluorescent dye was
observed with the naked eyes.
[0039] Regarding the print adhesive labels of Examples 1 to 3, the light emitting part by
the fluorescent dye through the adhesive labels could be confirmed. On the other hand,
regarding the print adhesive label of Comparative Example 1, the light emitting part
by the fluorescent dye through the adhesive label could not be confirmed.
Experiment 3: Confirmation of the designability of the adherend
[0040] The release sheets were removed from the print adhesive labels of Examples 1 to 3
and Comparative Example 1. The resulting adhesive labels were pasted on 50 µm thick
polyethylene terephthalate films (adherends) on which predetermined characters were
printed. The films in these state were observed with the naked eyes from the print
adhesive label side.
[0041] Regarding the print adhesive labels of Examples 2 and 3, all the characters printed
on the adherends could be read through the adhesive labels, and the designability
of the appearance of the adherends was not impaired at all. Moreover, regarding the
print adhesive label of Example 1, a part of the characters printed on the adherend
could be read through the adhesive label, and the designability of the appearance
of the adherend was not impaired. On the other hand, regarding the print adhesive
label of Comparative Example 1, the characters printed on the adherend could not be
read through the adhesive label, and the designability of the appearance of the adherend
was impaired.
INDUSTRIAL APPICABILITY
[0042] According to the present invention, a print adhesive label and an adherend using
the same, wherein the pasted security label is inconspicuous, and designability of
an adherend such as a product is not impaired, can be provided.
REFERENCE SIGNS LIST
[0043]
- 1
- label substrate
- 2
- adhesive layer
- 3
- adhesive label
- 4
- print layer
- 5
- release layer
- 6
- release sheet substrate
- 7
- release sheet
- 8
- adherend
- 9
- fluorescence dye